Handle Directories Ending in .jar

Currently, if the artifact being staged has directories ending in .jar they
are treated as archives unconditionally, causing error messages. This changes
causes the directories to be treated as they are, rather than artifacts.

[resolves #478]

Author: nebhale

lib/java_buildpack/framework/jrebel_agent.rb

@@ -59,7 +59,9 @@ def jrebel_configured?(root_path)
       end
 
       def jars_with_jrebel_configured?(root_path)
-        (root_path + '**/*.jar').glob.any? { |jar| !`unzip -l "#{jar}" | grep "rebel-remote\\.xml$"`.strip.empty? }
+        (root_path + '**/*.jar')
+          .glob.reject(&:directory?)
+          .any? { |jar| !`unzip -l "#{jar}" | grep "rebel-remote\\.xml$"`.strip.empty? }
       end
 
       def lib_name

lib/java_buildpack/jre/open_jdk_like_memory_calculator.rb

@@ -71,7 +71,8 @@ def supports?
       def actual_class_count(root)
         (root + '**/*.class').glob.count +
           (root + '**/*.groovy').glob.count +
-          (root + '**/*.jar').glob(File::FNM_DOTMATCH).inject(0) { |a, e| a + archive_class_count(e) }
+          (root + '**/*.jar').glob(File::FNM_DOTMATCH).reject(&:directory?)
+                             .inject(0) { |a, e| a + archive_class_count(e) }
       end
 
       def archive_class_count(archive)

spec/fixtures/framework_jrebel_jar_directory/dependency.jar/.gitkeep

@@ -44,12 +44,13 @@
 
     it 'does not detect when not enabled',
        app_fixture: 'framework_jrebel_app_simple' do
+
       expect(component.detect).to be_nil
     end
   end
 
   it 'downloads the JRebel JAR and the native agent',
-     app_fixture: 'framework_jrebel_app_simple',
+     app_fixture:   'framework_jrebel_app_simple',
      cache_fixture: 'stub-jrebel-archive.zip' do
 
     component.compile
@@ -59,7 +60,7 @@
   end
 
   it 'adds correct arguments to JAVA_OPTS',
-     app_fixture: 'framework_jrebel_app_simple',
+     app_fixture:   'framework_jrebel_app_simple',
      cache_fixture: 'stub-jrebel-archive.zip' do
 
     allow(component).to receive(:architecture).and_return('x86_64')
@@ -71,4 +72,12 @@
     expect(java_opts).to include('-Drebel.cloud.platform=cloudfoundry/java-buildpack')
   end
 
+  it 'does not throw an error when a directory ends in .jar',
+     app_fixture: 'framework_jrebel_jar_directory' do
+
+    expect_any_instance_of(described_class).not_to receive(:`).with(start_with("unzip -l #{app_dir + 'directory.jar'}"))
+
+    component.detect
+  end
+
 end

spec/fixtures/jre_memory_calculator_jar_directory/dependency.jar/.gitkeep

@@ -88,4 +88,13 @@
                             'Configuration: $CALCULATED_MEMORY && JAVA_OPTS="$JAVA_OPTS $CALCULATED_MEMORY"')
   end
 
+  it 'does not throw an error when a directory ends in .jar',
+     app_fixture:   'jre_memory_calculator_jar_directory',
+     cache_fixture: 'stub-memory-calculator.tar.gz' do
+
+    expect_any_instance_of(described_class).not_to receive(:`).with(start_with("unzip -l #{app_dir + 'directory.jar'}"))
+
+    component.compile
+  end
+
 end